DEVELOPMENT OF TISSUES AND OKGANS. 31 



cells connected by branching prolongations : in other cases the exten- 

 sions of the cells which, to be sure, have a very different function and 

 structure from those alreacty alluded to, but which, nevertheless, serve as 

 connections between cells so overbalance the cells in extent and number 

 that the latter often appear only as rounded swellings in the extensions 

 (e.g., in the nerves). (See Figs. 25 and 26.) 



FIQ. 26. NERVOUS GANGLIONIC CEL.L AND BRANCHING FIBRES, AFTER 

 KRAUSE. (Thanhoffer.) 



xt, cell body; m, nucleus; me, nucleolus; pn, protoplasmic prolongations; tf, axis-cylinder fibres; 

 tn, axis-cylinder prolongations. 



IV. THE DEVELOPMENT OF TISSUES AND ORGANS. 



The final result of the metamorphosis of cells is the formation of 

 tissues out of which the various organs of the body are built up. 



